442809062721 has 9 divisors (see below), whose sum is σ = 639615974179. Its totient is φ = 295204710936.

The previous prime is 442809062719. The next prime is 442809062747. The reversal of 442809062721 is 127260908244.

The square root of 442809062721 is 665439.

It is a perfect power (a square), and thus also a powerful number.

442809062721 is a `hidden beast` number, since 442 + 80 + 9 + 0 + 62 + 72 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 146616239025 + 296192823696 = 382905^2 + 544236^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 442809062721 - 2¹ = 442809062719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (442809062701) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1885411 + ... + 2107223.

Almost surely, 2^442809062721 is an apocalyptic number.

442809062721 is the 665439-th square number.

442809062721 is the 332720-th centered octagonal number.

It is an amenable number.

442809062721 is a deficient number, since it is larger than the sum of its proper divisors (196806911458).

442809062721 is an frugal number, since it uses more digits than its factorization.

442809062721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 443632 (or 221816 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The spelling of 442809062721 in words is "four hundred forty-two billion, eight hundred nine million, sixty-two thousand, seven hundred twenty-one".